Ethylene polymer, preparation process thereof and molded articles of the same

摘要

The present invention provides ethylene polymers capable of preparing various molded articles such as films, sheets or the like, and having excellent moldability, particularly excellent high-speed moldability. The ethylene polymers of the present invention have a density and molecular weight distribution in specific ranges. The first ethylene polymer is characterized by having (C) a ratio (MFR₁₀/MFR₂) of a melt flow rate (MFR₁₀) at 190° C. under a load of 10 Kg to a melt flow rate (MFR₂) at 190° C. under a load of 2.16 Kg of from 16.2 to 50. The second ethylene polymer is characterized by having (C) a ratio (MFR₁₀/MFR₂) from 12 to 50. The third ethylene polymer is characterized by having (D) a relation of omega2/omega1>=18 where omega1 and omega2 denote angular velocity (rad/sec) when complex elastic modulus G*(dyne/cm²) at 200° C. is 5.0x10⁵ dyne/cm² and 2.0x10⁶ dyne/cm², respectively, which are determined by measurement of the angular velocity dependence of the complex elastic modulus of the copolymer.